Session IX - Foot & Ankle

Saturday, October 14, 2000 Session IX, Paper #64, 11:05 am

Displaced Intra-Articular Calcaneal Fractures: Who Fails Treatment and Needs Subtalar Fusion?

Robert G. McCormack, MD; Richard E. Buckley, MD; Ross K. Leighton, MD; David P. Petrie, MD; Robert D. Galpin, MD; Marcel Csizy, MD; Graham C. Pate, MD, Four Level I Trauma Centers, Canada, Supported by OTA Research Grant

Objective: The goal of this study was to analyze the prospective clinical outcome of patients who have failed closed or open treatment for a displaced intra-articular calcaneal fracture. This cohort of patients required a secondary subtalar fusion by distraction bone block arthrodesis.

Design: Prospective randomized trial

Setting: Four level I trauma centers

Patients: Between April 1, 1991 and December 31, 1997, 424 patients with 471 displaced intra-articular calcaneal fractures were involved in a large multi-center randomized trial. Of these patients, 44, all with displaced intra-articular calcaneal fracture patterns, underwent a late subtalar fusion, 1 to 4 years after the initial treatment with either closed initial treatment or open reduction internal fixation (ORIF).

Intervention: Subtalar distraction bone block arthrodesis with tricortical bone graft was used in all 45 feet.

Main Outcome Measurements:

1. Radiographic fracture classifications

a. Böhler's angle

b. Essex-Lopresti classification

2. Computed tomography classification

a. Sanders

b. Crosby

3. Clinical scores

a. Validated visual analog score (VAS)

b. General health survey scores (SF-36)

c. Oral analog score (OAS)

d. Other factors - patient demographics including age, sex,

profession, smoking history and workers compensation

involvement. All fractures were classified as OTA 73-C1,

73-C2, 73-C3.


Results: Initial treatment of the 44 patients in our study was nonoperative in 37 (84%) patients and operative (ORIF) in 7 (16%) (one patient had bilateral heel fractures). Patients requiring fusion differed demographically >from those patients not requiring fusion. Mean age was 39 years in both fusion and non-fusion groups. The fusion group was 97% male, and the non-fusion group had 89% males. Sixty-four percent of the fusion patients made workers compensation claims, while 35% of the non-fusion group were claimants. Of those that required fusion, 77% were heavy laborers. On average, the fusion group had a Böhler's angle 15 degrees less than the non-fusion group. Forty-six percent of the fusion patients were Sanders type IV initial fractures. Logistic regression analysis revealed that the primary predictors of requiring fusion were wporkers compensation status (odds ratio = 3.03, 95% CI = 1.41-6.57), Sanders Class IV (odds ratio = 5.48, 95% CI = 1.57-19.18), Böhler's angle <0 (odds ratio = 10.64 - 95% CI = 1.33-85.17) and nonoperative initial treatment (odds ratio = 5.86 - 95% CI = 2.33-14.67).

Discussion: These data suggest that the amount of initial injury involved with the calcaneal fracture is the primary prognostic factor in long-term patient outcome. Böhler's angle on presentation of <0 was 10 times more likely to require a secondary subtalar fusion than a Böhler's angle on presentation of >15. Sanders Type IV calcaneal fractures were 5.5 times more likely to be fused than a simple Sanders Type II fracture. Workers compensation patients were 3 times more likely to be fused than other patients. Nonoperative care was 6 times more likely to lead to a late fusion as compared to ORIF treatment. Late fusion provided relief from pain and improved function, as evidenced by an improvement in VAS post-surgery.

Conclusion: This study demonstrates that a selected patient group with a displaced intra-articular calcaneal fracture is at high risk of fusion. These include male workers compensation patients who participate in heavy labor work with a fracture pattern with Böhler's angle less than 0 degrees. If their initial treatment was nonoperative, the likelihood of requiring late subtalar fusion was significantly increased. Initial ORIF of DIACF patients minimized the likelihood that subtalar fusion would be required.